Manufacturing methods to protect ULK materials from damage during etch processing to obtain desired features

Abstract

Embodiments are disclosed for processing microelectronic workpieces having patterned structures that include ultra-low dielectric constant (k) (ULK) material layers. In particular, embodiments are disclosed that deposit protective layers to protect ULK features during etch processing of patterned structures within substrates for microelectronic workpieces. For certain embodiments, these protective layers are deposited in-situ within the etch chamber.

What is claimed is: 
     
       1. A method of processing microelectronic workpieces, comprising:
 providing a substrate having a patterned structure that includes an organic layer and one or more ultra-low dielectric constant (ULK) features, the substrate being part of a microelectronic workpiece; 
 performing an etch process on the patterned structure to expose the one or more ULK features; 
 performing a deposition process to form a protective layer to protect the one or more ULK features; 
 performing an organic ash process to strip the organic layer, the protective layer protecting the one or more ULK features during the organic ash process; 
 performing an additional etch process to partially remove the protective layer, at least part of a remaining portion of the protective layer protecting the one or more ULK features at least in part during the additional etch process; and 
 performing at least another additional etch process to remove the remaining protective layer. 
 
     
     
       2. The method of  claim 1 , wherein the microelectronic workpiece is positioned within an etch chamber for a manufacturing system, and wherein the deposition process is performed without removing the microelectronic workpiece from the etch chamber. 
     
     
       3. The method of  claim 2 , wherein the deposition process comprises an atomic layer deposition (ALD) of an oxide-containing layer on the patterned structure. 
     
     
       4. The method of  claim 3 , wherein the oxide-containing layer is a SiO2 film. 
     
     
       5. The method of  claim 1 , wherein the organic ash process and the additional etch process each comprises a plasma etch process. 
     
     
       6. The method of  claim 1 , wherein the etch process comprises a via etch process to open one or more vias within the patterned structure adjacent the one or more ULK features. 
     
     
       7. The method of  claim 6 , wherein the additional etch process comprises a trench etch process to form one or more trenches and the one or more vias and to partially remove the protective layer, at least part of the remaining portion of the protective layer protecting the one or more ULK features at least in part during the trench etch process. 
     
     
       8. The method of  claim 1 , wherein a chamfer angle (0) is formed within a surface for one or more corners of the one or more ULK features. 
     
     
       9. The method of  claim 8 , wherein the chamfer angle (0) is formed such that 85°<0<90°. 
     
     
       10. The method of  claim 8 , wherein the chamfer angle (0) is formed such that 40°<0<85°. 
     
     
       11. The method of  claim 1 , wherein the protective layer is partially removed after the deposition process to leave one or more pillars protecting the one or more ULK features. 
     
     
       12. The method of  claim 11 , further comprising controlling a height for the one or more pillars using a thickness for the organic layer prior to the deposition process. 
     
     
       13. The method of  claim 12 , wherein the height for the one or more pillars is selected based upon a depth for the trench formed in the etch process. 
     
     
       14. The method of  claim 1 , wherein the organic ash process partially removes the protective layer to leave one or more protective plugs to protect the one or more ULK features. 
     
     
       15. The method of  claim 14 , wherein the protective layer is an organic film. 
     
     
       16. The method of  claim 1 , wherein the deposition process forms a thin protective layer that covers the patterned structure and partially fills the one or more vias. 
     
     
       17. The method of  claim 16 , wherein the thin protective layer is an organic film and wherein the organic ash process partially removes the thin protective layer. 
     
     
       18. The method of  claim 17 , wherein the deposition process and the organic ash process are cyclically repeated until the one or more vias are filled within the organic film leaving one or more protective plugs to protect the one or more ULK features. 
     
     
       19. The method of  claim 1 , wherein the organic ash process is performed to remove the organic layer before the deposition process is performed to form the protective layer. 
     
     
       20. The method of  claim 19 , wherein the organic ash process partially removes the protective layer to leave one or more protective plugs to protect the one or more ULK features. 
     
     
       21. The method of  claim 20 , wherein the protective layer is an organic film. 
     
     
       22. The method of  claim 1 , further comprising performing a metallization process to form a metal layer over the ULK feature. 
     
     
       23. The method of  claim 22 , wherein the metal layer comprises copper. 
     
     
       24. The method of  claim 1 , wherein the one or more ULK features have a dielectric constant (k) of 3.3 or less such that k<3.3. 
     
     
       25. The method of  claim 1 , wherein the one or more ULK features have a dielectric constant (k) of 2.0 to 3.3 such that 2.0<k<3.3.